Balancing-machine.



NICHOLAS W. AKIMOFFOF PHILADELPHIA, PENNSYLVANIA, ASSIGNOLI TO DYNAMIC BALANCING MACHINE COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A CORPORA- TION OF PENNSYLVANIA.

BALANCING-MACHINE.

Specification of Letters Patent. Patented ltgu', 11, 1919,

" Application led December 18, 1916, Serial No. 137,564. Renewed July 6, 1918. Serial No. 243,702.

To all 'whom it may concern n 'Be it known that I, NICHOLAS W.- AKI- Morr,a subject of the Czar of Russia, residing at Philadelphia, in the 'county of Philadelphia and State of Pennsylvania, have in-v vented certain new and useful Improvements in Balancing-Machines, of which the following is 'a specification.

The sclence of rigid dynamics contemplates various modes of constraints under which the motion-of bodies takes place, and

` said to each possess but one degree of freedom. An insect upon a level surface, a ship navigating upon the ocean, and a body mounted 'to revolve upon a sha-ft supported by yielding bearings, are all said to possess two degrees of freedom, while on vthe other hand, the chassis'of an automobile supported by resilient tireshas as many as six degrees of freedom.

Now a body can oscillate in just as many different and entirely independent manners as it possesses degrees of freedom, wherefore, a body havingtwo degrees of freedom is capable of vibrating' in two absolutely independent manners, with two entirely distinct periods of vibration. This coexistence (fa plurality of different oscillation consequently positively precludes the possibility ofy constructing a dynamic' balancing machine upon the basis of any principle except that limited to vibrate in but one degree. In this case, and 4this-case alone, one' is concerned with the eii'ect o f unbaflancc manifested in but one way, thereby avoiding all confusion or ambiguity in reading or interpretating the observations of the oscillations of an uiibalanced body. (For an explanation of the meaning of the dynamicwand static7 balance of rotatable bodies, see copending applications Serial Nos. 32.296 and 114,986.)

Indeed, it has often been proved in vactual practice, that, while a body balanced in a one-degree machine actually remains in balance when rotated in any other machine, a

body placed in apparent balance on a twodegree. machine invariably manifests vcry poor balance upon the present one-degree Atype of machine, until finally corrected for balance on the latter, after which'it of course i shows perfect balance on the former or any other machine, regardless .of the number of vthe degrees of freedom that the latter may possess. The very essence of a two-degree machine is based upon the discovery of a certain phase difference, between the periods of the two forms of vibration. which feature is a very elusive characteristic, in view of the above mentioned coexistence of two distinctly individual modes of oscillation.

A machine of but one degree of freedom is the only one that contemplates absolutely no elements of the nature of any pbase difterence. In this type of machine all unbalance is forced to make itself evident in one manner only, which makes it easy both to observe the effect and to estimate the extent thereof.l

Consequently. such a principle is the only logical onel that can be conceived of for satisfying the exacting demands of commercial requirements, and actual experience with apparatus of this kind, constructed to moet many different requirements has invariably confirmed the obvious correctness of Athis principle. Specifically, the present machine consists not only ofa correcting weight, or equivalent balancing body, of means for indicating vibrations, and of means wherebv the testing and balancing bodies are run in Synchronism, but of an oscillator having one degree of freedom only, especially constructed to positively manifest in a most rigid manner the presence or absence of both Static and dynamic unbalance..

The embodiment in a machine of such a principle in its broad sense permits of innumerable different arrangements or constructions, and it should not be considered that the following description of oneform 'of l'nechlanism implies the limitation of the said principle and its adaptation to only this narrow interpretation. but on the contraxv simply shows in a concrete manner one wav in which perfect results in the balancing` olf rotatable bodies can be accomplished. The complete illustration of this form of the machine comprises Figure l, which is a front elevation of' the device set for dynamic balancing; Fig. i2, is an end elevation of the sanie; Fig. 3. is a detail view of a balancing member; Fig. 1L is a front elevation of the y cal y while revolving; to indicate the degree device set for static balancing; and Fig. 5`is section on' the line 5-5 of Fig. 4.

The object of the invention,'as reduced to practice in the specific manner hereby disclosed, 1s-to provide a mechanism. operative to. .erfectly balance a rotatable body Statlof lack ofbalance inherent within said body, and the location. and amount of material necessary to be removed therefrom, or added thereto.; to provide a mechanism capable of. being quickly and easily transformed into a machine operative to perfectly balance a ro tatable 'bodyv dynamically while revolving; to provide a dynamic balancing machine operative to indica-te the degree of such bal` ange, and the location and amount of materiall 'necessary to be removed therefrom, or added' thereto; to provide in such a -uni- `versa] machine a. balancing unit comprising A a radially movable weight, operative to revolve vin synchronism with the body being tested, adjustable into didierent angular positions with respectto said body, rotatable uponau axis parallel with the axis said body when arranged for dynamic balancing tioned between the opposite. adjacent ends vof "thesaidrame and'oscillalbry members are 'compression springs 5 preferably having a predetermined and common natural period of vibration under n given load.

Upon lthe said oscillator is rotatably mounted a table 8, supported by legs 9 above hand formingvan integral part of a rim .10, the outer peripheral ,edge of which is mov able circumferenti-a'lly Within a ring 11 firmly, secured 'to the oscillator and prevented from xvertical movement with respect thereto by an nivel-hanging flange 12, bolts 155 also being provided in said -rim for se- Acuring said table ina given angular position. 'lo bring the said table and support ing members intol a given position with 4re- 'spec't to saidv oscillator,- graduations may be .provided on; the Harige 12, o r in any other well known manner. f

To the upper surface of the table 8 is secured a head stock 15, through which extends a shaft 16, carrying a pulley 17, a belt orchain connecting said pulley to a second pulley lll carried by ajsh'aft 19, in turn supported byyhangers 20 from the under side of the said jfable, to the inner en! of the position on the yoke 36.

threaded bar toward one If with. a definite displacement this cor- 'i A rects the unbalanced condition of the said f stock 26, 'remov voi vably secured in a given position by a clamp 27 and forming a bearing for the end 28 of shaft 16, while between said headvand tail'. 'stocks upon said shaft a body 29, which is being tested, motion being impartedto said body through the shafts, belt,`and bevel gears abovedescribed, the lower end oftheA shaft 23 being provided with a; bevel gear 31,

meshing with a gear fixed to a shaft Said shaft 33 is supported by hangers 34 from the under side of the oscillator 3,.and is driven by a motor 35, While upon one end is Vsecured a yoke 36, between the parallel" arms 37 of which extends a threaded rod. 38, carrying in threaded engagement therewith a spool 39, preferably lmurled at its end portions. By Virtue of the relationeel` the gears extending between the. motor and the revoluble support for the body being tested, the yoke 36 revolves chronism with" the said body, whether they rotate in one direction or the-other.

in absolute syni' When operating this device as a static balancing machine, the table is rotated into a position in which the axis of perpendicular to the lplane of vibrationI of the oscillator, as shown inFigs. 4 and 5. This is generally done before proceeding to' dynamically balance a given'body, and if the latter lacks perfect static balance, when rotated on this l brates With the spool or Weight in a central n While continuing to rotate in exact synchronism with the body, thev weight `is shifted upon the endof the yoke.

body the --vibration of thefoscillator ceases, a quantity of material is added to, the body as indicated .by the degrec of displacement of the said weight and the angular position of the said yolfeavith respect to the body. However', if the unalance is not overcome completely, thema# chine is stopped and of the yoke altered, or

the body Y is machine the oscillator vitaken from,j or

the angular position. this may be accomplished while still rotating by the use of anazimuth changing mechanism such as that described in copending application, Serial A readjustment of the said weight is again made until a position isA` found at which all which material is removed or addedjas above mentioned.

In the operation of this device chine for deternining the dynamic balance lof a' rotatable body, the latter is arranged as shown .in Figs. 1 and 2, essentially with vibration ceases, after' as a nur' 'i lil() its axis of rotation lying in a plane coincident with the plane of vibration of the oscillator. The spool 39 is placed first in a. central position, and with the yoke having a given angular relation with respect to the said body, and if upon starting up the mechanism the .oscilla-tor u ibifates, the said spool is moved toward oneffif the yoke arms by means of frictionallylingaging the knurled portions of the former.

This shifting of the spool,'or balancing weight, may counterbalance a heavy point 1n the body and thereby cause the oscillator to stop vibrating, such movement on its part being directly caused by a heavy point on the said body, or an equivalent in the form of a light point on the side dia-metrically opposite thereto. However, if such movement ofthe weight does not neutralize the said unbalanced condition, or if it only partially does so, the angular relation of the said yoke withrespect to the said body may be changed, by stopping the mechanism, or

by providing such an azimuth changing dcvice as above referred to, after which the same procedure is renacted until thel unbalanced condition is-completely neutralized, when the machine is brought to a stop and a portion of the body filed or drilled therefrom to the extent, and in the position, indicated respectively by the displacement' from center, and angular relation, of the said Weight and yoke with respect thereto.

Having thus described f, my invention, what claim and desire to protect by Let-I ters Patent of the United States is l. A balancing machine, comprising an oscillator limited to'one degree of freedom. a rotatable support for the body to be tested carried by saidoscillator, and means also carried by said oscillator and rotatably associated with the said support,vand operative to test the dynamic or static balance of a body thereupon. y

2. A combined static and dynamic balancimgl machine, comprising an oscillator. a rotatable support mountedk thereon and adapted to receive a body to be tested, means to impose upon said oscillator a forced vibration of any desired frequency and amplitudc, and4 means to move said support and said tirst means in synchronism.

A combined static and dynamic balancing machine. comprising an oscillator, a rotatable support mounted thereon and adapted to receive a body to be tested. means to impose upon said oscillator a forced yibration of any desired frequency and amplitudc. means to shift the axis of rotation of said. support at an angle to and parallel with the axis of oscillation of said first means, and means to move said support and said first means in synchronism.

A dynamic and static balancing machlne, comprising an oscillatory base, a turntable carried thereby, and a rotatable support carried by said turntable and adapted to receive a body to be tested.

5. A `dynamic and static balancing machine, comprising an oscillatory base, a turntable carried thereby, a rotatable support carried by said turntable and adapted to receive a body to be tested, a weight, means whereby said weight is revolubly carried by said base, and means operative to drive s'aid supportand said weight-carrying-means in synchronism.

' 6. A dynamic and static balancing machine, comprising an oscillatory base, a turntable carried thereby, a rotatable support carried by said turntable and adapted to receive a body to be tested, a weight, means whereby said weight is revolubly carried by said base and is adapted to be shifted with respect to its axis of rotation, and means to drive said support and said weight-carrying means in synchronism.-

7. A dynamic and static balancing machine, comprising an oscillatory base, a turnf 'table carried thereby, a rotatable support carried by said turntable and adapted to receive a body to be tested, a weight, means whereby said weight is revolubly carried by said base and adapted to be shifted with respect to its 'aXis of .rotation while said support and said weight, are in motion, and

means to drive said support and said weightcarrying means .in synchronism.v

8. A dynamic and static balancing mabchine, comprising an oscillatory base, a turn` table carried thereby. va rotatable support carried by said turntable and adapted to re- `ceive a body to be tested, a weight., means whereby said weight is revolubly carried by said base and is adapted to be shifted transversely of its axis of rotation while -said support and saidl 'weight are in motion and means to drive said support and said weightcarrying means in synchronism.

9. A balancing machine. comprising an' oscillator limited to one degree of freedom. a support for rotatably supporting the body to be tested and carried by said oscillator. means also carried by said oscillator, and connections whereby said means is rotated in harmony with a body upon said support, the whole being operative to test the dynamic or static balance ot a body.

1t). A combined dynamic and static balancing machine, comprising an oscillator. a support mounted thereon and adapted to receive a body to be tested, rotatable means to impose upon said oscillator a forced vibration of any desired frequency and amplitude, and'means to rotate a body upon said support and said first means in synchronism.

1.1. A combined dynamic and static balancing machine. comprising an oscillator.' a suppoit mounted thereon and adapted to receive a body to be tested, means to imposa upon said oscillator a forced vibration of any desired amplitude, and means to rotate a body upon said support and to operate said first means in harmony.

I2. A balancing machine, comprisingl an oscillatory mounting, means tor rotatably supporting` a body to be tested and carried by said mounting, statically adjustable means also carried by said mounting, and connections whereby said last means is moved in 'harmony with a body upon said first means, the whole being operative to test the balance of a body upon said first means.

13. A balancing,r machine, comprising' an. oscillatory `mounting, means for rotatably supporting a body to be tested and carried by saidmounting, rotatable radially adjustable means valso carried by said mounting and operative to impose upon said mounting a variable forced vibration, to neutralize the viln'ation'iinposed upon said mounting by a body when unbalanced and rotating upon said support, and connections whereby said last means is made to rotate in synchronism with, and operative to test the balance of, ay body upon said first means.

14.. A. combined dynamic and static balancing machine, comprisingr an oscillator, a Support mounted thereon and adapted to ro'- tatably receive a body to be tested, and rotatable means connected with and operative to impose upon said oscillator a forced vibration of any desired amplitude, and connected to rotate in synch-ronism with a body upon said support, to counteract unbalanre ot such body.

15. The method which consists in infwfhanically associating a dynamically unbalanced body with a body adapted to be perfectly balanced and unbalanced statically at will so that each tends to oppose the tenth-nov ot' the other to vibrate il unludaiu'cd. and so that the two may be revolved synchroumisly,

thus forming an unbalanced system, and

then adjusting said last-named body to neutralize the unbalanced condition of'said first body to balance said system.

1G. The method which consists in mechanically associating a dynamically unbalanced body with a body adapted to be perfectly balanced and unbalanced at will statically by radially shifting its center of gravity, so that each tends to oppose the tendency ot the other to vibrate if unlnilanced. and so that the two may be revolved synchronously, thus forming an unbalanced system, and then adjusting said last-named body to neutra iize the unbalanced condition of said first body to balance said system.

17. The ,method ivhieh consists in mechanically associatingT a statically ingoalanced body with a body adapted to be 'perfectly balanced and unbalanced statically at will j upon an oscillatory mounting. so thatI each tends to oppose the tendency of the other to vibrate if unbalanced` and so that theI two muy be revolved synchronmxsly. thus formingr an unbalanced system, and then adjusting said last-named body' to neutralize the unbalai'iced condition ofi said first body to balance said system.

18. The method which consists in mechanically associating` a statically unbalanced body ".vith a body adapted to be perfectly balanced and unbalanced statically at Will upon an oscillatory mounting, so that each tends to oppose the tendency of thc other to vibrate it' unbalanced, and so that the tivo may be revolved synchronously, thus forming.r an unbalanced system. and then adjusting said last-named body to neutralize the unbalanced condition of said first bod)r to balance said system.

ln testimony whereof l have Aaflixed my signature.

NICHOL S Vv'. KIMOFF. 

